Articles generally require significant coverage
in reliable sources
We need significant coverage. This helps show that a topic meets the notability guidelines. We need multiple sources that discuss the topic directly and in detail. Not: passing mentions, directory listings, or any old thing that happens to have the topic's name in it.
We need sources that are reliable. Usually this means that the publisher has a reputation for fact checking and the text must be approved by an editor before it is printed. Choose: books from reputable publishing houses, mainstream newspapers, or other periodicals. Not: tabloids, discussion boards, fansites, Facebook, YouTube, or most blogs. (Some blogs are written by professional journalists and published on newspaper websites, but most blogs have no editorial oversight, and comments on blogs, like forum posts, are almost never ok.)
We need sources that are independent from the subject of the article. Not: articles written by the topic (including interviews), paid for by the topic, their website, or their organization. Not a press release written by a publicist that puts a positive "spin" on a subject and omits negative incidents. Not a report put out by an organization owned by the subject. We want readers to be able to rely on what they read, and to be able to verify claims they read in Wikipedia articles. So, please add footnotes to your article citing reliable sources such as recognized experts on the subject or trustworthy reporters, best if published in mainstream media or in books and journals printed by reputable publishers.